1. Field of the Invention
This invention relates to folding hand tools in which a blade or working member pivots to be enclosed in protective sheath which forms a handle when the tool is in use, and relates especially to folding knives, and specifically to an improved device for moving and locking the blade with a single hand.
2. Description of the Related Art
Folding knives have been around for millennia. Modern pocket knives have used springs and locks to hold blades in an extended, open position for use or in a folded, closed position within a handle for storage. Springs have become the primary mechanism to open or retract the blade back into the handle. However, springs have their disadvantages. Springs may apply excess, unneeded force to open or close the folding tool. Springs also wear over time and may also make the folding tool more dangerous to use.
In inventions where springs were removed, folding knives commonly require two hands and a great deal of strength and dexterity to unfold. Other inventions have sought to harness the power of the spring to also provide for easy access to a blade. These inventions which have sought to allow for single-handed implementation have commonly required spring-loaded buttons or ever more complicated mechanisms. In these knives, the buttons for opening or closing the blade are designed to be used in only one hand, usually the right hand, but they are not designed for equal use in either hand.
Even with the assistance of springs and locks, most knives still either require two hands to operate or a specific hand. Two hands or a specific hand are not always available to properly operate these knife features. Improper use of such mechanisms may make knives more hazardous to use in certain circumstances. Despite the centuries of work on perfecting the folding knife, the mechanisms available today are still too cumbersome and dangerous to be used by individuals with handicaps or otherwise limited dexterity. An improved folding knife tool is needed.